1. Field of the Invention
The present invention relates to a signal transfer apparatus of a computer, and more particularly, to a signal transfer apparatus capable of transferring information at a high transfer rate to a display from a main system frame in which a computer system is installed.
2. Description of the Related Art
A conventional laptop computer shown in FIG. 1 comprises a main system frame 10 in which a computer system is installed, a display 11 for displaying various information from the main system frame 10, and a keyboard 12 for inputting various information and commands.
The display 11 may be a liquid crystal display device (LCD) or a plasma display panel (PDP). In recent years, a need for large and high-resolution displays has increased. Also, the amount of data transferred to the display 11 from the main system frame 10, and the data transfer rate have increased.
In the conventional computer, a cable 15 made of metal wire as shown in FIG. 2 is used to transfer an information signal from the main system frame 10 to the display 11. The information signal, i.e., a transistor transistor logic (TTL) signal, is transferred from the main system frame 10 to the display 11 through the cable 15, and the display 11 displays the received information or images according to the transferred signal.
As another conventional method, low-voltage differential signaling (LVDL) is used as shown in FIG. 3. In detail, the TTL signal output from the main system frame 10, i.e., a parallel pixel data, is converted into low-power serial data by a LVDS transmitter 20, and then transferred through the cable 25. The transmitted serial data is converted into a parallel TTL signal by a LVDS receiver 27 situated in the display 11. The display 11 then displays an image according to the TTL signal.
Such signal transfer between the main system frame 10 and the display 11 of the conventional computer is achieved through the metal cable 15 or 25 whose transfer characteristics depend on a R-C time constant. However, the signal transfer rate is limited because the R-C time constant has a critical value. Thus, the metal wire cable 15 or 25 cannot satisfy the requirements for an increase in both the amount of data transferred and the transfer rate. Also, when an information signal is transferred through a metal wire, it is very likely that electromagnetic interference (EMI) will occur.
When the LVDS is adopted, it is not possible to achieve a long-distance transfer, such as a transfer of an information signal to an extra external display, because the LVDS is driven at a comparatively low voltage, e.g., approximately 350 mV.
To solve the above problems, it is an object of the present invention to provide a signal transfer apparatus of a computer, capable of transferring a signal at a high rate between a main system frame and a display without electromagnetic interference, and capable of achieving a long-distance signal transfer between the main system frame and an external display.
According to an aspect of the present invention, there is provided a signal transfer apparatus of a computer, comprising: a substrate installed in a main system frame of the computer; a driving device installed on the substrate, for converting a video signal into a current signal; a semiconductor laser array for emitting light corresponding to the current signal from the driving device; an optical fiber bundle for transferring the light emitted from the semiconductor laser array to a display; a photo receiver array for converting the light transferred through the optical fiber bundle into a current signal; and a converter for converting the current signal output from the photo receiver array into a video signal.
According to another aspect of the present invention, there is provided a signal transfer apparatus of a computer, comprising: a substrate installed in a main system frame of the computer; a driving device installed on the substrate, for converting a video signal into a current signal; a semiconductor laser array for emitting light corresponding to the current signal from the driving device; a beam splitter for splitting the light emitted from the semiconductor laser array; a first transfer portion including a first optical fiber bundle for transferring a part of the light split by the beam splitter to a first display, a first photo receiver array for converting the light transferred through the first optical fiber bundle into a current signal, and a first converter for converting the current signal output from the first photo receiver array into a video signal; and a second transfer portion including a second optical fiber bundle for transferring another part of the light split by the beam splitter to a second display, a second photo receiver array for converting the light transferred through the second optical fiber bundle into a current signal, and a second converter for converting the current signal output from the second photo receiver array into a video signal.
According to still another aspect of the present invention, there is provided a signal transfer apparatus of a computer, comprising: a substrate installed in a main system frame of the computer; a driving device installed on the substrate, for converting a video signal into a current signal; first and second semiconductor laser arrays for each emitting light corresponding to the current signal of the driving device; a first transfer portion including a first optical fiber bundle for transferring the light emitted from the first semiconductor laser array to a first display, a first photo receiver array for converting the light transferred through the first optical fiber bundle into a current signal, and a first converter for converting the current signal output from the first photo receiver array into a video signal; and a second transfer portion including a second optical fiber bundle for transferring the light emitted from the second semiconductor laser array to a second display, a second photo receiver array for converting the light transferred through the second optical fiber bundle into a current signal, and a second converter for converting the current signal output from the second photo receiver array into a video signal.